Diurnal pattern of protein and energy metabolism in man
Open Access
- 1 September 1980
- journal article
- research article
- Published by Elsevier in The American Journal of Clinical Nutrition
- Vol. 33 (9), 1983-1986
- https://doi.org/10.1093/ajcn/33.9.1983
Abstract
Rates of synthesis and breakdown of body protein and oxidation of leucine were measured in six obese subjects by constant intravenous infusion of (114C)leucine for 24-hr periods. During the night, when no food was given, the rate of whole body protein synthesis was 67% of the rate observed during the day, when food was given hourly. By contrast the rate of body protein breakdown remained constant over the full 24 nr. This resulted in the immediate deposition of about 30% of the protein intake during the day, whereas the remaining 70% was immediately oxidized. At night the rate of protein oxidation fell to only 38% of its daytime value. The rate of oxygen consumption also decreased at this time so that the contribution of protein oxidation to total energy expenditure fell from 27% during the day to 13% at night. These changes reflect the normal, discontinuous pattern of food intake and the need during feeding to store protein in tissues for use in subsequent periods of fasting.This publication has 5 references indexed in Scilit:
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